Add "In Group x" for Groups Sub Forums Posts

yzc_add_in_group_for_groups_sub_forums_posts.php

<?php

/**
 * Add "In Group x" for Groups Sub Forums Posts
 **/
function yzc_add_in_group_for_groups_sub_forums_posts( $activity_text, $user_id, $topic_id, $forum_id  ) {

    // Get Parent Forum
    $parent_forum_id = bbp_get_forum_parent_id( $forum_id );

    if ( empty( $parent_forum_id ) ) {
        return $activity_text;
    }

    // Get Parent Forum Data.
    $forum_permalink = bbp_get_forum_permalink( $parent_forum_id );
    $forum_title     = get_post_field( 'post_title', $parent_forum_id, 'raw' );
    $forum_link      = '<a href="' . $forum_permalink . '">' . $forum_title . '</a>';

    // Edit Action Text.
    $activity_text .= ' in the group ' . $forum_link;

    return $activity_text;

}

add_filter( 'bbp_activity_topic_create', 'yzc_add_in_group_for_groups_sub_forums_posts', 10, 4 );